Here's how he describes the number of iPhones Apple sold last
holiday season.

"If you stacked all of the phones — you know how thin they are,
an iPhone 6 — if you stacked them like pancakes, not only would
they be taller than the tallest building, they would go up a few
hundred miles, such that they would be higher than the orbit of
the International Space Station."

Apple sold those 74 million iPhones in just 90 days — and it's
Williams' job to make sure all of those iPhones get manufactured
and shipped properly. Williams has been referred to as "Tim
Cook's Tim Cook" since he's in charge of Apple's supply chain,
one of the areas Cook was in charge of overseeing as Apple's COO
before being promoted to CEO.